I feel more professional when wearing more formal clothes and I think people are more likely to view me as more mature. I think I have pretty good sense of fashion, but when it comes to wearing abercrombie and aeropostale and all those pretty boy preppy flock mentality clothes, no thank you! I do dress a little nerdy (or more positively, more mature), but I am absolutely aware of the stylishness of my choices. I would rather dress a little more proffesional because thats who I am. Recently I got a bunch of buttoned shirts because I had mostly tshirts before, and I decided to really start dressing professionaly more, especially considering I'll be out in the work place soon. And I just feel better in formal.
umm, I have worn socks and sandals in the past because its comfortable. I don't think thats an aboslute fashion no no if you like it. If you can avoid it, yeah, but if you feel comfortable with your fashion overall, theres nothing wrong with doing a few things that aren't "right".